Bay Networks 4000, Справочное руководство

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Bridging and Frame Filtering
118814-D Rev. 00 11-11
Parameter: Value
Options: A value to match in hex
Function: When matching parts of a packet it is important to enter
exactly what you are matching against. The value allows
you to do just this. Used in conjunction with the Mask
parameter, it allows you to match against a specific value
at a specific mask location.
Instructions: In the following example, we have entered a mask of 80,
specifying that we want to match a value in position 8 of
the first half of a byte:
The value that we want to match here is 0. The value
entered into the Value parameter then is 00. This
specifies that we want to match a zero against the first
position of the byte as specified in the Mask parameter.
In this next example, a mask value of 96 has been
entered. The mask specifies that we are checking
positions 8 and 1 in the first half of the byte and
positions 4 and 2 in the second half:
Using this mask, we want to match a 1 in position 8 and
a 0 in position 1 of the first half of the byte and a 0
against position 4 and 2 in the second half. The value
entered here (in hex) is 80.